mongodb与SQL常见语句对照

inert into users value(3,5)	db.users.insert({a:3,b:5})
select a,b from users	db.users.find({}, {a:1,b:1})
select * from users	db.users.find()
select * from users where age=33	db.users.find({age:33})
select a,b from users where age=33	db.users.find({age:33}, {a:1,b:1})
select * from users where age=33 order by name	db.users.find({age:33}).sort({name:1})
select * from users where age>33	db.users.find({age:{$gt:33}})
select * from users where age!=33	db.users.find({age:{$ne:33}})
select * from users where name like "%Joe%"	db.users.find({name:/Joe/})
select * from users where name LIKE "Joe%"	db.users.find({name:/^Joe/})
select * from users where age>33 and age<=40	db.users.find({'age':{$gt:33,$lte:40}})
select * from users order by name desc	db.users.find().sort({name:-1})
select * from users where a=1 and b='q'	db.users.find({a:1,b:'q'})
select * from users limit 10 skip 20	db.users.find().limit(10).skip(20)
select * from users where a=1 or b=2	db.users.find( { $or : [ { a : 1 } , { b : 2 } ] } )
select * from users limit 1	db.users.findOne()
select order_id from orders o, order_line_items li where li.order_id=o.order_id and li.sku=12345	db.orders.find({"items.sku":12345},{_id:1})
select customer.name from customers,orders where orders.id="q179" and orders.custid=customer.id	var o = db.orders.findOne({_id:"q179"}); var name = db.customers.findOne({_id:o.custid})
select distinct last_name from users	db.users.distinct('last_name')
select count(*y) from users	db.users.count()
select count(*y) from users where age > 30	db.users.find({age: {'$gt': 30}}).count()
select count(age) from users	db.users.find({age: {'$exists': true}}).count()
create index myindexname on users(name)	db.users.ensureIndex({name:1})
create index myindexname ON users(name,ts desc)	db.users.ensureIndex({name:1,ts:-1})
explain select * from users where z=3	db.users.find({z:3}).explain()
update users set a=1 where b='q'	db.users.update({b:'q'}, {$set:{a:1}}, false, true)
update users set a=a+2 where b='q'	db.users.update({b:'q'}, {$inc:{a:2}}, false, true)
delete from users where z="abc"	db.users.remove({z:'abc'});